Cleaning apparatus

ABSTRACT

A frame of a cleaning apparatus accommodates a unit which comprises a reservoir for a foamable liquid and a distributor trough unitary with the reservoir and adapted to receive foamable liquid therefrom. Mounting portions are provided for removably mounting the unit in the frame. A foaming unit is provided which converts the liquid received in the distributor trough into foam. Brush rollers are provided on the frame so that the latter can roll on these rollers over a surface to be treated with the foam, and the brush rollers turn when the frame moves over the surface and transmit motion to the foaming unit which causes the same to foam the liquid in the distributor trough.

[ Aug. 7, 1973 United States Patent 1191 Lei eit

[ CLEANING APPARATUS 3,614,801 10/1971 Peabody 15/179 [75] Inventor: Gamer Lemma, Nassau/Lab, 3,623,177 11/1971 Pack........ 15/50 R Germany Primary Examiner-Edward L. Roberts AttorneyMichael S. Striker Nassau/Icahn, Germany 1 ABSTRACT A frame of a cleaning apparatus accommodates a unit 22 Filed: Jan. 18, 1972 Appl. No.: 218,809

which comprises a reservoir for a foamable liquid and a distributor trough unitary with the reservoir and Foreign Application Priority Date Jan. 19, 1971 Germany...................

adapted to receive foamable liquid therefrom. Mountbe treated with the foam and the brush rollers turn when the frame moves over the surface and transmit motion to the foaming unit which causes the same to foam the liquid in the distributor trough.

3 3 0C2 0/ 101 I150 5 4 7R. 4 9 m U mm9 In ""5 "U1 1 "v. Hu HH un mmh .c "fir "U I hf C Uhm 11]] 2 8 555 References Cited UNITED STATES PATENTS 3,114,922 Ballantyne l5/50 R 3,212,117 10/1965 Ernstberger et al. 15/50 R 19 Claims, 5 Drawing Figures PATENIEL AUG 1 ms SHEET 1 OF 3 ENTEnms Hm 3.750223 SHEET 2 BF 3 1 *A MI 5O BACKGROUND OF THE INVENTION The present invention relates generally to a cleaning apparatus, and more particularly to an apparatus for producing a cleaning foamand applying it to a surface to be treated.

Generally speaking, such apparatus has a reservoir which contains a foamable liquid in unfoamed state, and a foaming unit receiving liquid from the reservoir and converting it into foam which is then applied to the surface to be treated. It is not believed to be necessary to discuss the construction and operation of such apparatus in detail because it is already known to those skilled in the art. However, reference may be had for further information to copending applications Ser. Nos. 881,440, now US. Pat. No. 3,696,458, and 884,623 now US. Pat. No. 3,623,176 both of which disclose details of such apparatus.

It is known in such prior-art apparatus to accommodate the various components of the apparatus in a rigid housing which can only be opened at the top in order to gain access to the reservoir so that the latter can be filled, emptied or the like. Unfortunately, such a construction requires relatively large expenditures of material and relatively complicated and therefore expensive assembly operations. Moreover, if a defect occurs in these prior-art constructions, in which the housing is largely closed except for the accessibility at the top to the reservoir, this frequently means that the entire cleaning apparatus must be discarded so that under certain circumstances a total loss of the apparatus can occur very quickly after it has been placed into service, for instance if it is not handled carefully. Repairs, particularly if the apparatus is made of synthetic plastic material, are not usually practicable or, if carried out, not usually satisfactory.

SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide an improved cleaning apparatus of the type hereunder discussion.

More particularly it is an object of the present invention to provide such an improved cleaning apparatus which can be produced with substantial savings in material and assembly time.

An additional object of the invention is to provide such an improved cleaning apparatus in which, in the event defects should occur, a repair and restoration of the apparatus to serviceability can be readily effected by simple replacement of the defective component.

In pursuance of these objects and of others which will become apparent subsequently, the present invention resides in a cleaning apparatus which, according to one embodiment and briefly stated, comprises a frame and a unit comprising reservoir means for a foamable liquid and distributor means unitary with the reservoir means and adapted to receive foamable liquid therefrom. Mounting means removably mounts the unit in the frame. Converting means is associated with the reservoir means for conversion into foam of liquid received by the distributor means. Rolling means is provided on the frame for rolling displacement of the same over a surface to which foam is to be applied. This rolling means is associated with the converting means for effecting operation of the same in response to rolling displacement of the frame.

This construction, it will be seen, provides for a clear separation between those components of the apparatus which accommodate the foamable liquid and supplied to the converting means, and thus the installation and also the removal of individual parts is greatly facilitated thereby. Furthermore, the reservoir means in particular is usually constructed as a hollow inherently strong body which resists deformation, so that the separate frame can be relatively weak in its construction and therefore requires comparatively little material, because it only needs to provide for the support of the various components, especially journalling of the turnable components, whereas it need not provide for rigidity of the apparatus which is assured by the rigidity of the reservoir itself.

In order to provide both for a stable and reliable arrangement of the individual components in the frame, and on the other hand for facilitating the connection of the frame with the various components, it is advantageous if the frame has rigid lateral portions and elastically deflectable longitudinal portions, all of which are of one piece. It is advantageous if the unit of reservoir means and distributor means can be inserted into the frame from the. lower open side thereof, that is the side which in operation of the apparatus faces the surface to be treated, and if a connection is a snap action connection. Cooperating abutment shoulders may be provided on the frame and on the unit and this provides for a very considerable stability of the assembled apparatus. Moreover, assembly of an apparatus so constructed is extremely simple and rapid, and the same is true of disassembly of the various components.

According to a further concept of the invention the unit comprising the reservoir means and the distributor means may be of two parts, each of which is composed of one half of the reservoir means and one half of the distributor means. The advantage of such an arrangement is that the halves can be readily produced, especially the hollow interior of the half of the reservoir means, with relatively simple tools and for instance of synthetic plastic material by molding. Moreover, before these halves are then rigidly connected with one another any components which are desired to be accommodated in the interior of the reservoir means -for instance a float or the like which provides for metered dispensing of the liquid from the reservoir means to the distributor meanscan be introduced before the two halves are joined. Also, the filling opening for the reservoir means can be located wherever desired and its position is not dictatedas before by considerations of having to be able toinsert such components into the interior of the reservoir means through the tilling opening.

It is advantageous if the underside of this unit is so constructed that it can constitute the bottom of the apparatus when the unit is assembled in the frame. This avoids the necessity for providing a separate bottom panel for the apparatus. Advantageously recesses are provided in the bottom wall of the unit into which the rolling elements of the rolling means may in part extend, and at least some of these rolling elements may be joumalled at one axial end in the frame and in the other axial end in journals provided in the unit itself. This means that a further connection is established between the frame and the unit via the rolling elements and it is thus no longer necessary to have the rolling elements extend from one side of the frame to the other to be journalled in the two sides. Thus, the rolling elements need not be as long as would otherwise be necessary with a concomitant increase in the freedom of choice as to where the rolling elements should be located and journalled.

The journals for the rolling elements and the elements of the converting means are to facilitate assembly and disassembly advantageously provided in form of sockets with downwardlythat is towards the surface to be treated open inserting channels which converge towards the socket so that shafts of the rolling elements and of elements of the converting means can be inserted with a snap action, for which purpose the portionsof the journals are advantageously elastically yieldable. The insertion is therefore readily accomplished by pressing portions of the shafts in radial direction into the respective sockets with a snap action, without requiring the use of any tools or the like. Moreover, by having the inserting channels open in downward direction, the weight of the cleaning apparatus will reliably maintain the portions of the shafts in the respective sockets at all times.

Transmission of motion from the rolling elements to the converting means is advantageously effected by utilization of gear drives, preferably located at the outer axial ends of the respective driving and driven components, that is rolling elements of the rolling means and rotatable elements of the converting means. It is also advantageous if the rolling elements of the rolling means are configurated in form of cylindrical brush rollers which are advantageously constructed with a rigid core over which there is slipped an elastically distendable sheath or jacket provided with bristles of one piece with it. In this manner excellent surface contact of the rolling elements is obtained, even if the cleaning apparatus is of low weight, and at the same time reliable assurance is provided against any damage to the surface during turning of the rolling elements. It is particularly advantageous if the sheath provided with the bristles is in form of a plurality of individual annular portions each provided with some of the bristles, which annular portions are then axially arrayed on the rigid core, not only because such relatively short in axial directionannular portions are more simple to produce than longer tubular sheaths, but also because they can be inexpensively and individually replaced if localized wear occurs. In addition, the resistance through wear is increased by the construction of the rolling elements in the aforementioned manner.

It is advantageous if the rolling elements are located at the respective lateral sides of the distributor means and at that end of the reservoir means which is remote from the distributor means. This is an arrangement which provides for a stable support of the cleaning apparatus on the one hand, and on the other hand it affords motion transmission to the converting means from several rolling elements which have good contact with the surface over which they move.

It is further advantageous, according to another concept of the invention, to provide a cladding unit which surrounds the frame at least at the outer side thereof and can be releasably connected with it by a snap action coupling. The purpose of this cladding unit is to prevent threads or similar matter which might be present on the surface to be treated, from entering into the journals for the turnable components, the gear transmission and possibly also in the distributor, that is into locations where they could cause trouble in the operation of the apparatus. A cover may be provided cooperating with the cladding unit and overlying the frame at the upper side thereof but leaving at least the filling opening for the reservoir means free. Thus, the components are protected also against the entry of possible contaminants from above. It is advantageous to provide the cover with at least one viewing window so located that the converting means may be viewed and its operation thus supervised. The cover should be readily releasable as well as being readily connectable, so that its release and connection can be carried out even by persons who have no mechanical skill and aptitude, because it is desirable that the user be capable of gaining access from time to time to some of the components, especially the converting means, for cleaning and other purposes.

The apparatus may be provided with a substantially U-shaped bracket having arms the free ends of which are pivotably connected with the frame so that they can pivot about an axis which extends substantially parallel to the surface to be treated. Connected to this bracket, that is to the bight thereof which is located upwardly above the frame and the cover if such is provided, may be a threaded nipple for securing of a handle by means of which the apparatus may be moved over the surface to be treated. If a cladding unit is provided, then the latter should be provided with suitable recesses for the arms so that the latter can pivot in the aforementioned manner. With such an arrangement the force exerted upon the apparatus to effect its movement over the surface to be treated, that is the force exerted via the handle, is transmitted directly upon the frame which carries the rolling elements and the cladding element and the unit comprising the reservoir means and the distributor means receive either no force or only a negligible force.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to'its construction and its method of operation,

together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 5 is a perspective view of a rolling element of the apparatus in FIGS. 1-4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing now in detail it will be seen that in FIG. 1 I have illustrated a cleaning apparatus according to the present invention; this apparatus is identitled in tote with reference numeral 10 and serves for the production and application of a cleaning foam. The apparatus 10 is to be moved over a surface to be treated, for instance over a carpet or the like, to which the foam is to be applied.

Reference numeral 12 identifies a substantially U- shaped or C-shaped bracket having two arms the end portions of which are pivotabiy connected with the frame 21 of the apparatus, and the bight of this bracket 12 carries for instance a threaded nipple 11 to which a non-illustrated handle may be connected. It will be appreciated that in accordance with conventional practice a push or a pull is exerted on this handle in order to displace the apparatus on the surface to be treated.

in FIG. 1 the cover 13 has been shown removed from the apparatus, being shown in a raised position so as to permit viewing of the interior of the apparatus. The cover 13, which is clearly visible in FIG. 1, is of substantially C-shaped outline, being downwardly open and having side wall portions 14 which overlap in the assembled condition the front and rear sides of the apparatus. The portions 14 are provided with beads 15 which in'the assembled condition of the cover 13 will be received with a snap action in correspondingly configurated (not separately identified) grooves provided in a cladding element 17 which clads the outer side of the frame 21. The edges 18 of the cover 13 are proof the frame 21, with these edge portions 20 extending inwardly beyond the cladding element 17. Thus, the

cover 13 is retained by a snap'action in the confines of the cladding element 17. It is provided with an opening 22 which in the assembled condition registers with a filling opening 23 of a reservoir 24, through which the latter may be provided with foamable liquid in unfoamed state so that it is not necessary to remove the cover 13 when additional liquid is to be introduced into the reservoir. A viewing window 25 is advantageously also provided on the cover 13, either in form of a cutout, in form of an opening provided with a plastic or glass windowpane, or perhaps even in form of a transparent portion of the cover 13 itself, if for instance the cover 13 is made of synthetic plastic material which is suitably opaqued everywhere else-except at the por tion 25. in any case, however, the purpose of the viewing window 25 is such that it permits observation of the operation of the converting or foaming unit 26, so that it is possible at all times to ascertain that foam is prop-' erly being produced by the same.

-As FIGS. 1 and 4 show particularly clearly, the converting means or foaming unit 26 utilizes in the illustrated embodiment three rollers 27 and 28 which may have rigid cores and be coated or provided with layers of elastically compressible cellular foam plastic. The

roller 28 is located between and in a somewhat lower level than the rollers 27 and in such relationship therewith that upon relativerotation of these rollers along the lines of contact between them there will occur incremental compression of the foam plastic. This, in turn, will be followed by relaxation of the just compressed increment of the foam plastic and in accordance with well known principles this will result in foaming of the foamable liquid.

As FIG. 4 shows, there are provided gear transmissions utilizing gears 29 fixedly connected with the rollers 27 and gears 30 which are fixedly connected with the rolling elements 31 and 32. The gears 29 and 30 mesh so that, when the rolling elements 31 and 32 turn as they move on and over a surface to be treated, motion is transmitted via the gears 30 and 29 to the rollers 27 which in turn transmit rotary motion frictionally to the roller 28. This results in the aforementioned incremental compression of the foam plastic material of the rollers 27 and 28, and in the formation of foam due to the intensive admixture of liquid on the foam material with air, whereby an almost dry foam is produced.

The liquid for production of this foam is supplied to the unit 26 via a trough-shaped distributor 33 of slightly upwardly convex configuration in at least one part, with the roller 28 being accommodated in the convexity as illustrated in FIG. 4. The roller 28 is journalled at its opposite axial ends in journals provided in the distributor itself so that it is supported over its entire length by the distributor 33 and is thus capable of uniformly absorbing the cleaning liquid which enters the distributor 33.

The cleaning liquid is received by the distributor 33 from the reservoir 24 via a channel 35 which can be closed by means of-a flap or member 34. The channel 35 and lateral-webs 36 connect the reservoir 24 with the distributor 33 so that the two form a rigid structural unit as shown clearly in FIG. 3. FIG. 2 shows that this unit also constitutes the bottom wall of the apparatus 10 so that a separate or bottom wall panel is not necessary. it is advantageous if, as illustrated in the exemplary embodiment, the unit composed essentially of the reservoir 24 and the distributor 33 is composed of two transverse halves 37 (see FIG. 3) whose line of separation is designated with reference numeral 8 in FIG. 3. Thus, each of the halves 37 is composed of one half of the reservoir 24 and one half of the distributor 33 and may be readily produced in one piece of synthetic plastic material in accordance with known techniques. Such a construction makes it simple to insert desired components (not illustrated) into the hollow interior of the reservoir 24, for instance a suitable valve or the like which controls the flow of liquid through the channel 35) whereupon the two halves 37 are then fluidtightly and rigidly connected alongthe line of separation38. Such connection can be carried out, for instance, by heat welding .or by adhesive means or the like. lf'desired, the mating edges of the two halves 37 may be provided with tongue and groove connections.

The unit which is essentially composed of thereservoir 24 and the distributor 33 (and of-course of the channel 35 and the webs 36) is inserted from below -that is from the side which normally faces the surface to be treated into the frame 21. FIG. 3 shows that the reservoir 24 is provided with shoulders 40 which in the inserted condition will contact and be supported by the underside of the portions 20 on the side wall portions 41 of the frame 21. These portions 41 are rigid, that is not readily deformable, and serve further for the journalling of the rollers 27 and of the rolling elements.

By contrast to the side wall portions 41 of the frame 21, the longitudinal wall portions 42 of the frame 21 that is the wall portions at the front and rear sides of the apparatus have a certain amount of elasticity, that, is they can yield to some extent. The reservoir 24 is provided with a downwardly directed shoulder 43 as shown in FlG. 4 which can slide past the rearward longitudinal wall 42 when the unit 24 and 33 is inserted into the frame 21, so as to rest on the upper edge of this longitudinal wall portion 42 in the inserted condition. Projections 44 are provided at the lateral sides of the distributor 33 and cooperate with portions 45 of the frame 21 which also have a limited ability to elastically yield and which are provided with recesses 46 in which the projections 44 can be matingly received with a snap action.

FIG. 3 shows clearly that the side wall portions 41 of the frame 21 are provided with journals 47 and 48 for journalling of the rollers 27 and of the rolling elements. The sockets of the journals 47 are configurated as illustrated and the openings are of somewhat lesser diameter than the diameter of the pins or shafts to be journalled in them, being slightly elastically yieldable so that these pins or shafts can be inserted with a snap action in radial direction. The openings face substantially downward direction, that is towards the surface to be treated when the cleaning apparatus is in use, so that any bearing pressures resulting from use of the apparatus are taken up in the upper regions of the journals 47.

As shown in FIGS. 1, 2 and 3 the foaming rollers 27 as well as the roller element 31 which is located at the front side of the apparatus, extend over the entire width of the apparatus 10. Because of this they are journalled at their opposite axial ends in the side wall portions 41 of the frame 21. The rolling elements 32, however, are shorter as is clearly shown in FIG. 2. They are located in the region of the reservoir 24 for which purpose the latter is provided in its bottom wall with suitable hollows or recesses 49 (see FIG. 3) in which the rolling elements 32 are partly accommodated. A comparison of FIGS. 2 and 3 also shows that for each of the rolling elements 32 there is provided one journal 50 on the underside of the reservoir 24 itself, whereas the other journal for the same rolling element 32 is respectively provided in one of the side wall portions 41 of the frame 21.

The rolling elements 32 (just as the rolling element 31) have rigid cores as will be discussed later, and because of this rigidity the connection of the rolling elements 32 both with the reservoir 24 and the frame 21 provides for 'a further structural connection between the frame and the unit composed of the reservoir 24 and the distributor 33. Additionally, further rolling elements 39 similar to the rolling elements 32 but of lesser axial length are provided at the rear side of the apparatus 10, being mounted in the same manner as the rolling elements 32, that is journalled at one axial end in journals 50 provided in the reservoir 24 and at the other axial end in journals provided in the side wall portions 41 of the frame 21.

Attention is directed to FIG. 5 in connection with the above comment that the rolling elements 31, 32 and 39 have rigid cores. FIG. 1 shows that in the illustrated embodiment the rigid core is cylindrical and identified with reference numeral 7, being surrounded by a sheath or tubular jacket 56 provided with a plurality of outwardly extending bristles. It is advantageous, but not necessary, that the sheath 56 be composed of a plurality of individual annular portions each having some of the bristles and being axially arrayed on the core 57. The material of the sheath 56 and of the bristles which advantageously are of one piece with it, is preferably a relatively soft elastically yieldable synthetic plastic material.

It was pointed out earlier that the free ends of the arms of the bracket 12 are pivotably connected with the frame 21, for which the latter is provided with the illustrated journals which are not, however, provided with a separate reference numeral. Thus, the bracket 12 can pivot about a horizontal axis, that is an axis which extends in parallelism with the surface over which the apparatus moves, a measure which is already known from the prior art and which permits displacement of the apparatus over the surface which is to be treated by pushing or pulling on the handle. However, inasmuch as the bracket 12 is pivoted to the frame 21, which latter is exteriorly surrounded by the cladding element 17, the latter must be provided with openings or cutouts 52 and 53 through which the arms of the bracket 12 can extend so that they can pivot without difficulty, and furthermore in order to permit a simple connecting of the cladding element 17 with the frame 21 even after the bracket 12 has already been pivotably connected with the frame. The conection of the cladding element 17 with the frame 12 is a snap-coupling connection, as has been pointed out before, and it will be seen in FIG. 1 that the wall portions 42 of the frame 21 are provided with projections 54 which interengage with beads 55 which are elastically deformable and provided on the cladding element 17 with which they afford a snap-coupling connection.

Naturally, the illustrated embodiment is to be considered as being exemplary only, and modifications in construction and configuration of the various components can be made and will offer themselves to those skilled in the art, without departing from the spirit and intent of the invention.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a cleaning apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can byapplying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by letters Patentis set forth in the appended claims:

1. A cleaning apparatus, comprising a frame which includes a pair of at least substantially parallel rigid side wall portions and a pair of elastically yieldable at least substantially parallel longitudinal wall portions extending between and of one piece with said side wall portions; a unit comprising reservoir means for a foamable liquid and distributor means unitary with said reservoir means and adapted to receive foamable liquid therefrom; mounting means removably mounting said unit in said frame; converting means associated with said reservoir means for conversion into foam of liquid received by said distributor means; and rolling means on said frame for rolling displacement of the same over a surface to which foam is to be applied, said rolling means being associated with said converting means for effecting operation of the same in response to rolling displacement of said frame.

2. An apparatus as defined in claim 1, said mounting means comprising cooperating snap couplings on said frame and said unit.

3. An apparatus as defined in claim 1, said frame having an open side which faces downwardly toward a surface to be treated when said apparatus is in use; and wherein said unit is insertable into said frame through said open side, and said side wall portions have upper edge regions provided with abutments for engagement by said unit when the latter is inserted into said frame through said open side.

4. An apparatus as defined in claim 3, said abutments projecting inwardly of said frame on the respective side wall portions of the same, and said unit having abutment shoulders for engagement with said abutments.

5. An apparatus as defined in claim 1, said mounting means comprising a part of one of said longitudinal wall portions of said frame and a shoulder provided on said reservoir means and adapted for snap-action engagement with said part in response to insertion of said unit into said frame, and said mounting means further comprising projections provided on said distributor means and elastically yieldable lobes provided on said side wall portions and having sockets adapted to receive said projections with a snap action.

6. An apparatus as defined in claim 5, further comprising bevelled surfaces provided on at least some of said part, said shoulder, said projections and said lobes for facilitating snap-action coupling thereof.

7. An apparatus as defined in claim 1, said unit being composed of two fixedly connected lateral halves each constituting part of said reservoir means and part of said distributor means.

8. An apparatus as defined in claim 1, said unit having a bottom wall which faces said surface when said apparatus is in use, and which constitutes the bottom wall of said apparatus.

9. An apparatus as defined in claim 8, said rolling means including a plurality of rolling elements; and wherein said bottom wall has an outer side provided with depressions for partial accommodation of respective ones of said rolling elements.

10. An apparatus as defined in claim 9; and further comprising a plurality of pairs of journal portions for said rolling elements, each pair including one journal portion provided on said frame and an other journal portion provided on said unit.

11. An apparatus as defined in claim 1; and further comprising gear transmission means interposed between and operatively associated with said converting means and said rolling means.

12. An apparatus asdefined in claim 1, said rolling means comprising a plurality of rolling elements at least some of which include a rigid core portion and an elastically yieldable sleeve portion surrounding said core portion and being formed with outwardly projecting bristles.

13. An apparatus as defined in claim 12, wherein said sleeve portion is composed of a plurality of annular sections which are axially arrayed on said core portion.

14. An apparatus as defined in claim I, distributor means having lateral sides, and said reservoir means having one side closer to and intermediate said lateral sides and an other side further from said distributor means; and wherein said rolling means comprises a plurality of rolling elements located adjacent said lateral sides and said other side, respectively.

15. An apparatus as defined in claim 1; further comprising a cladding element for cladding at least the exterior of said frame; and cooperating snap couplings on said frame and cladding element for releasable connection of the latter with said frame.

16. An apparatus as defined in claim 15, said cladding element having an open side which faces upwardly when said apparatus is in use, and said reservoir means having an inlet opening for said foamable liquid facing said open side; and further comprising a cover removably connectable with said cladding element and overlying said open side but having said inlet opening exposed.

17. An apparatus as defined in claim 16, said cover being provided with a receiving part for viewing of said converting means when said cover overlies said open side.

18. An apparatus as defined in claim 15; further comprising a substantially U-shaped bracket having a pair of arms provided with free ends which are respectively pivotally connected to said frame at opposite lateral sides thereof, said cladding element having respective cut-outs through which said arms extend.

19. A cleaning apparatus, comprising a frame; a unit comprising reservoir means for a foamable liquid and distributor means unitary with said reservoir means and adapted to receive foamable liquid therefrom; mounting means removably mounting said unit in said frame; converting means including converting rollers associated with said reservoir means for conversion into foam of liquid received by said distributor means; rolling means including rolling elements on said frame for rolling displacement of the same over a surface to which foam is to be applied, said rolling means being associated with said converting means for effecting operation ofthe same in response to rolling displacement of said frame; and a plurality of journal portions for said rollers and rolling elements, at least some of said journal portions being provided on said frame and each including a socket and an elastically distendable passage which communicates with the respective socket and diverges in direction towards an open side of said frame which in use of said apparatus faces downwardly towards said surface.

I. i t l I 

1. A cleaning apparatus, comprising a frame which includes a pair of at least substantially parallel rigid side wall portions and a pair of elastically yieldable at least substantially parallel longitudinal wall portions extending between and of one piece with said side wall portions; a unit comprising reservoir means for a foamable liquid and distributor means unitary with said reservoir means and adapted to receive foamable liquid therefrom; mounting means removably mounting said unit in said frame; converting means associated with said reservoir means for conversion into foam of liquid received by said distributor means; and rolling means on said frame for rolling displacement of the same over a surface to which foam is to be applied, said rolling means being associated with said converting means for effecting operation of the same in response to rolling displacement of said frame.
 2. An apparatus as defined in claim 1, said mounting means comprising cooperating snap couplings on said frame and said unit.
 3. An apparatus as defined in claim 1, said frame having an open side which faces downwardly toward a surface to be treated when said apparatus is in use; and wherein said unit is insertable into said frame through said open side, and said side wall portions have upper edge regions provided with abutments for engagement by said unit when the latter is inserted into said frame through said open side.
 4. An apparatus as defined in claim 3, said abutments projecting inwardly of said frame on the respective side wall portions of the same, and said unit having abutment shoulders for engagement with said abutments.
 5. An apparatus as defined in claim 1, said mounting means comprising a part of one of said longitudinal wall portions of said frame and a shoulder provided on said reservoir means and adapted for snap-action engagement with said part in response to insertion of said unit into said frame, and said mounting means further comprising projections provided on said distributor means and elastically yieldable lobes provided on said side wall portions and having sockets adapted to receive said projections with a snap action.
 6. An apparatus as defined in claim 5, further comprising bevelled surfaces provided on at least some of said part, said shoulder, said projections and said lobes for facilitating snap-action coupling thereof.
 7. An apparatus as defined in claim 1, said unit being composed of two fixedly connected lateral halves each constituting part of said reservoir means and part of said distributor means.
 8. An apparatus as defined in claim 1, said unit having a bottom wall which faces said surface when said apparatus is in use, and which constitutes the bottom wall of said apparatus.
 9. An apparatus as defined in claim 8, said rolling means including a plurality of rolling elements; and wherein said bottom wall has an outer side provided with depressions for partial accommodation of respective ones of said rolling elements.
 10. An apparatus as defined in claim 9; and further comprising a plurality of pairs of journal portions for said rolling elements, each pair including one journal portion provided on said frame and an other journal portion provided on said unit.
 11. An apparatus as defined in claim 1; and further comprising gear transmission means interposed between and operatively associated with said converting means and said rolling means.
 12. An apparatus as defined in claim 1, said rolling means comprising a plurality of rolling elements at least some of which include a rigid core portion and an elastically yieldable sleeve portion surrounding said core portion and being formed with outwardly projecting bristles.
 13. An apparatus as defined in claim 12, wherein said sleeve portion is composEd of a plurality of annular sections which are axially arrayed on said core portion.
 14. An apparatus as defined in claim 1, distributor means having lateral sides, and said reservoir means having one side closer to and intermediate said lateral sides and an other side further from said distributor means; and wherein said rolling means comprises a plurality of rolling elements located adjacent said lateral sides and said other side, respectively.
 15. An apparatus as defined in claim 1; further comprising a cladding element for cladding at least the exterior of said frame; and cooperating snap couplings on said frame and cladding element for releasable connection of the latter with said frame.
 16. An apparatus as defined in claim 15, said cladding element having an open side which faces upwardly when said apparatus is in use, and said reservoir means having an inlet opening for said foamable liquid facing said open side; and further comprising a cover removably connectable with said cladding element and overlying said open side but having said inlet opening exposed.
 17. An apparatus as defined in claim 16, said cover being provided with a receiving part for viewing of said converting means when said cover overlies said open side.
 18. An apparatus as defined in claim 15; further comprising a substantially U-shaped bracket having a pair of arms provided with free ends which are respectively pivotally connected to said frame at opposite lateral sides thereof, said cladding element having respective cut-outs through which said arms extend.
 19. A cleaning apparatus, comprising a frame; a unit comprising reservoir means for a foamable liquid and distributor means unitary with said reservoir means and adapted to receive foamable liquid therefrom; mounting means removably mounting said unit in said frame; converting means including converting rollers associated with said reservoir means for conversion into foam of liquid received by said distributor means; rolling means including rolling elements on said frame for rolling displacement of the same over a surface to which foam is to be applied, said rolling means being associated with said converting means for effecting operation of the same in response to rolling displacement of said frame; and a plurality of journal portions for said rollers and rolling elements, at least some of said journal portions being provided on said frame and each including a socket and an elastically distendable passage which communicates with the respective socket and diverges in direction towards an open side of said frame which in use of said apparatus faces downwardly towards said surface. 